Patent GB-1218103-A (GB)
Title: Combine harvester
IPC: A01D41/127
Filed: 1968-04-16
Abstract: 1,218,103. Combine harvester. DEERE & CO. 16 April, 1968 [14 April, 1967], No. 17997/68. Heading A1F. A combine harvester has an engine which drives its wheels and crop conveyer 8 through first and second change speed mechanisms respectively and is characterized in that the conveyer 8 has a device 17-25 which measures the change in throughput of crop, whereby the conveyer speed or both the speed of the conveyer and the speed of travel can be regulated so that a uniform thickness of crop-layer is fed into the thresher. The crop conveyer 8 can deflect about 19 with the variation of crop-layer thickness passing below it and this deflection is transmitted through arms 17 and link 21, to an adjusting lever 23 which can close the switches 129 or 131 to operate an electromagnetic valve 57 so as to regulate the conveyer speed. When the crop-layer thickness exceeds a desired value, the conveyer deflection transmitted to lever 23 closes the switch 129 and fluid under pressure flows from the valve 57 to a cylinder 50 through a pipe 53 to drive the piston rod 51 out, thereby the distance between the shaft 41 (driven by engine 31) and the shaft 45 carrying a double V-belt pulley 46 increases. The double pulley 46 (Fig. 2, not shown) is such that when the effective diameter of its portion engaged by belt 49 decreases due to increase in distance between the shafts 41 and 45, the effective diameter of the portion engaged by belt 87 increases; and vice versa. The pulley 89 driven by belt 87 is such that its diameter adjusts itself in accordance with the adjustment of the double pulley 46. The conveyer speed thus increases when the piston rod 51 is diven out. When the rod 51 is out by a certain amount, a lever 133 secured to the rod operates a switch 135 which breaks the circuit and stops the valve 57 from further driving out the piston rod 51. If the lever 23 closes the switch 131 instead of the switch 129, the piston rod 51 is driven in and the conveyer speed decreases. A warning light 137<SP>1</SP> is put in the circuit to inform the harvester driver when the conveyer speed is increasing and it goes out by operation of the switch 135 stated above. If the crop-layer thickness passing below the conveyer increases further due to increase of travel-speed of the combine, the lever 23 further closes a switch 141 to re-operate the valve 57 so that the piston rod 51 is further driven out to break the circuit. The conveyer speed again corresponds to the crop-layer thickness. When the crop-layer thickness passing below the conveyer reaches a maximum value, the lever 23 operates a limit switch 145 to operate an electro-magnetic valve 112 through a cable 146 and also to light up a warning light 137 to warn the driver that the maximum throughput of the crop has been reached and that the regulating operation has begun. The valve 112 sends fluid under pressure to a cylinder 107 through the pipe 109 to drive the piston 117 in. Thus the distance between the engine-pulley 37 and the double belt pulley 46<SP>1</SP> (similar to pulley 46) decreases and thus the speed of travel reduces. The driver can also reduce (or increase) the travel speed of the combine by closing a hand-switch 121 between a cable 123 (or 125) so as to operate the valve 112 so that the piston rod 117 is driven in (or driven out). In another embodiment (Fig. 4, not shown) the travel speed and the conveyer speed can be increased or decreased simultaneously so that the threshing mechanism is constantly fed with a uniform crop thickness.